1. Field of the Invention
The present invention relates to a controller for an internal combustion engine.
2. Description of the Related Art
In internal combustion engines (hereinafter referred to as engines) such as diesel engines mounted on vehicles or the like, when an actual heat generation rate at the time of combustion (the amount of heat generated per unit rotational angle of a crankshaft: dQ/dθ) is obtained, and when there is a difference between the actual heat generation rate and a reference heat generation rate, engine control parameters are corrected. For example, in a technique described in Japanese Patent Application Publication No. 2005-320872 (JP 2005-320872 A), an actual heat generation rate is estimated from in-cylinder pressure detected by an in-cylinder pressure sensor, and when there is a difference between a tilt angle (actual heat generation rate gradient) of rising of the actual heat generation rate and a tilt angle (reference heat generation rate gradient) of rising of the heat generation rate in a standard condition, the supply pressure of fuel is corrected such that the difference is eliminated.